//-------------------------------------------------------------
//  While.java    Author:YanYuJun
//
//---------------------------------------------------------------
  import java.util.Scanner;
    public class While
     {
       public static void main(String[]args)
        {
           int n=1,n1;
           Scanner scan=new Scanner(System.in);
          System.out.println("Enter n:");
           n1= scan.nextInt();
           int n2 =1;
           int n3 =1;
           while(n2 <=n1)
              {
               n3 *= n2*n1;
               n1--;
              }
           System.out.println(" n!:" +n3);
         }
       }
